Synthesis of AgInS2 QDs in droplet microreactors: Online fluorescence regulating through temperature control

For the synthesis of AgInS₂ quantum dots (QDs), a suitable temperature is extremely important for control of the size, shape and fluorescence properties of QDs. Most of synthesis methods for AgInS₂ QDs are based on batch reactors, which bring uneven distribution of temperature, affecting their fluorescence properties and size uniformity. Here we designed a droplet microreactor with a temperature-controllable region, and successfully synthesized water-soluble AgInS₂ QDs. By accurately controlling temperature, we also studied how the reaction temperature affected the fluorescence properties of AgInS₂ QDs. The results showed that with the increasing of reaction temperature, the QDs size increased and the fluorescence peak constantly red-shifted along with enhanced fluorescence intensity. Based on the droplet microreactor, we could achieve more appropriate reaction condition to synthesize AgInS₂ QDs with higher fluorescence quantum yield (QY) and intensity.